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Cited by 455

The DOI matches its Crossref record; 35 of the 35 references it cites were found in a registry or an index.

Mechanism of leg stiffness adjustment for hopping on surfaces of different stiffnesses

Farley, Claire T., Houdijk, Han H. P., Van Strien, Ciska, Louie, Micky·1998·Journal of Applied Physiology
DOI 10.1152/jappl.1998.85.3.1044
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Abstract

When humans hop in place or run forward, leg stiffness is increased to offset reductions in surface stiffness, allowing the global kinematics and mechanics to remain the same on all surfaces. The purpose of the present study was to determine the mechanism for adjusting leg stiffness. Seven subjects hopped in place on surfaces of different stiffnesses (23–35,000 kN/m) while force platform, kinematic, and electromyographic data were collected. Leg stiffness approximately doubled between the most stiff surface and the least stiff surface. Over the same range of surfaces, ankle torsional stiffness increased 1.75-fold, and the knee became more extended at the time of touchdown (2.81 vs. 2.65 rad). We used a computer simulation to examine the sensitivity of leg stiffness to the observed changes in ankle stiffness and touchdown knee angle. Our model consisted of four segments (foot, shank, thigh, head-arms-trunk) interconnected by three torsional springs (ankle, knee, hip). In the model, an increase in ankle stiffness 1.75-fold caused leg stiffness to increase 1.7-fold. A change in touchdown knee angle as observed in the subjects caused leg stiffness to increase 1.3-fold. Thus both joint stiffness and limb geometry adjustments are important in adjusting leg stiffness to allow similar hopping on different surfaces.

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Metadata

Authors
Farley, C. T., Houdijk, H. H. P., Van Strien, C., & Louie, M.
Venue
Journal of Applied Physiology
Publisher
American Physiological Society
Published
1998-09-01
Volume
85
Issue
3
Pages
1044-1055
ISSN
  • 0161-7567 (ISSN-L)
  • 8750-7587
  • 1522-1601
DOI
10.1152/jappl.1998.85.3.1044
OpenAlex
W2174295199
Cited by
455
References
35
FWCI
6.15
Type
journal article
Language
en
Open access
closed

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CoChat. (2026). Citation check: Mechanism of leg stiffness adjustment for hopping on surfaces of different stiffnesses. https://app.cochat.ai/papers/10.1152/jappl.1998.85.3.1044
The paper
Farley, C. T., Houdijk, H. H. P., Van Strien, C., & Louie, M. (1998). Mechanism of leg stiffness adjustment for hopping on surfaces of different stiffnesses. Journal of Applied Physiology. https://doi.org/10.1152/jappl.1998.85.3.1044

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Bibliographic data: Semantic Scholar, OpenAlex, Crossref.

Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.